Synchronous motor electric audible signal clock



J. BROWN Nov. 15, 1955 SYNCHRONOUS MOTOR ELECTRIC AUDIBLE SIGNAL CLOCK Filed Feb. 8, 1954 3 Sheets-Sheet 1 James Drawn Nev. 15, 1955 J BROWN SYNCHRONOUS MOTOR ELECTRIC AUDIBLE SIGNAL CLOCK Filed Feb. 8, 1954 3 Sheets-Sheet 3 Jame Brown JQLLJE- United States Patent 'Ofihce 2,723,526 Patented Nov. 15, 1955 SYNCHRONOUS MOTOR ELECTRIC AUDIBLE SIGNAL CLOCK James Brown, Toronto, Ontario, Canada Application February 8, 1954, Serial No. 408,926

11 Claims. (Cl. 58-38) This invention is directed to improvements in electric audible signal clocks such as strike clocks, chime 'clocks, and combined strike and chime clocks, and relates in particular to improvements in the striking or chiming mechanisms of electric clocks driven by continuously rotating synchronous motors.

The principal object of the invention is to provide a simple and reliable audible signal electric clock wherein the time keeping movement and the audible signal movement are both driven by the constantly rotating gear wheel of a continuously rotating synchronous electric motor; the single driven wheel of the audible signal movement being brought into and out of mesh with the constantly rotating gear wheel in the operation of the audible signal.

A further and particular object of the invention is to form the driven wheel of the audible signal with one or more gaps in its teeth, so that when such gaps are opposite the teeth of the constantly rotating motor gear wheel, the driving connection between the synchronous motor and the signal movement is broken; a star wheel and lever mechanism being incorporated in the time keeping movement and through the action of which the gapped wheel is partly rotated to bring its teeth into mesh with the constantly rotating gear of the motor, the gapped wheel rotating to operate the audible signal until its next gap moves into position to break the mesh between the teeth.

With the foregoing and other objects in view as shall appear, the invention consists of an audible signal starting and stopping mechanism for electric clocks all as hereinafter more particularly described, and illustrated in the accompanying drawings, in which:

Figure l is a rear or inside view of the back face of the front plate of an electric chime and striking clock movement showing the star wheel and lever mechanism for bringing the audible signal driven wheel into mesh with the constantly rotating clock driving synchronous motor gear.

Figure 2 is a front or inside view of the front face of the back plate of the movement, the view showing the constantly rotating gear wheel of the synchronous clock driving motor, together with the gapped chime and strike operating wheels which intermittently mesh therewith, and a rack strike release arrangement operated by the rotation of one of the gapped wheels.

Figure 3 is an enlarged horizontal cross-sectional view taken through the line 33, Figure l or Figure 2.

Figure 4 is a side elevational view of the striking driven gear wheel formed with a single gap, the view being taken through the line 44, Figure 3.

Figure 5 is a side elevational view of the chime driven gear wheel formed with four gaps spaced apart with increasing sequence to provide the chiming time for the first quarter, half hour, three quarters, and hour respectively, the view being taken through the line 55, Figure 3.

Figure 6 is a rearelevationalview of a portion of the back face of the back plate, and upon which is mounted a spring pawl to engage one of four peripheral notches in a steady disc rotatable with the chime mechanism, for the purpose of retaining the chime gear wheel inactive against vibration or jarring between chiming periods; the view being taken from the line 6-6, Figure 3.

Figure 7 is a similar view to Figure 1, showing two single pointed star wheels and lever arrangement for a striking clock, and

Figure 8 is an enlarged horizontal cross-sectional view taken through the line 8-8, Figure 7.

Like characters of reference indicate corresponding parts in the different views of the drawings.

In general, a clock of the type in which my invention is incorporated is driven by a continuously rotating synchronous electric motor 2 carried upon the back face of the back plate 3 of the movement and having a continuously rotating arbour 4 which extends through the back plate and carries a driving gear wheel 5. In the most modern synchronous motor arrangements the gear wheel 5 makes one revolution per minute. The motor gear wheel 5 drives the clock hands through a suitable train of gears, which are not shown as they form no part of the invention outside of the sleeve 6 on the second hand spindle 7 which makes one revolution per hour.

The construction shown in Figures 1 to 6 illustrates the application of my invention to a chime and striking clock movement. Referring to Figure l, the four pointed star wheel 8 mounted upon the sleeve 6 makes one revolution per hour whereby the four points of the wheel, rotating in a counterclockwise direction, make contact with the pin 9 on the drop arm 10 to swing such arm upwardly into the position shown in dotted lines every fifteen minutes, the arm falling downwardly when the engaging star wheel point passes from underneath the pin 9.

A spindle 11 extends through aligned orifices in the back and front plates 3 and 3A and projects rearwardly of the back plate to carry the chime pin wheel as shall be further described. A star wheel 12 is secured to the spindle 11 and is positioned in substantially the same vertical plane as the arm It), the wheel being formed with a spacer bushing 13 which is secured to the spindle as by the set screw 14. The spindle 11 also carries a chime actuating gapped gear wheel 15 which rotates in unison with the star wheel 12, as also does the chime pin wheel 16 positioned upon the spindle 11 exteriorly of the back plate. Standard type chime hammer arms 17 are positioned underneath or adjacent to the pin wheel 16 whereby rotation of the pin wheel causes its pins 18 to contact and swing the hammers whereby they strike the gongs (not shown), to produce the chime sound.

Upon reference to Figure 5 it will be seen that the gear wheel 15 is formed with four gaps 19 in its teeth, the gaps being spaced apart with increased sequence to provide the chiming time for the first quarter, half hour, three quarters, and hour respectively as the wheel partially rotates from one gap to another.

The operation of the foregoing described chiming arrangement is very simple. As the star wheel 8 rotates under the action of the running of the clock from one fifteen minute period to another, it lifts the arm 10 from the position shown in full lines in Figure l to the posi tion shown in dotted lines, and as the arm carries a swingable weighted plunger element 20 depending from its outer end, such element is raised with the upward movement of the arm and drops downwardly therewith from the position shown in dotted lines to the position shown in full lines when the engaging point of the star wheel .8 passes from under the pin 9 of the arm.

The star wheel 12 is formed with four point seats 21 and when the clock is running from one quarter to the next, the star wheel remains stationary in substantially the position shown in Figure 1. As the clock approaches a quarter the movement of the star wheel 8 lifts the arm 10 so that the lower end of the plunger 20 is swung upwardly around the adjacent point 21 to the dotted position thereabove. When the arm 10 and plunger 20 fall, the lower end of the plunger impacts the seat of the star point therebeneath, which action partly rotates the star wheel and spindle 11, whereby the chime gear wheel carried upon the spindle 11 is partly rotated from its stationary position with one of its gaps opposite the teeth of the continuously rotating driving gear 5, as illustrated in Figure 5, to a position wherein the teeth of the driving gear engage the teeth on the chime gear to partially rotate it until the next gap passes into position opposite the driving gear, whereby the meshing of the teeth is broken. As the spindle 11 turns in unison with the partial rotation of the chime gear, the chime pin wheel 16 also partly rotates to actuate the hammers 17 to produce the chime.

When a striking mechanism is incorporated with a chime mechanism a second gapped strike driving gear wheel 22 is mounted to rotate upon a bushing 23 secured to the back plate and through which the spindle 11 freely extends. As will be seen upon reference to Figure 4, the striking gear is formed with a single gap 24 as it only rotates at each hour to actuate the hour striking mechanism.

A standard striking cam wheel 25 and rack lift cam wheel 26 are mounted upon the sleeve 23 on either side of the striking gear wheel 22, being connected thereto by posts 27, whereby the striking gear wheel, striking cam wheel and rack lift cam wheel rotate on the sleeve 23 as a unit.

Referring to Figures 3 and 5, the face of the chime gear wheel 15 opposite to the face of the striking cam 25 carries a C-spring 28 having a lug 29 which makes contact with a lug 30 on the striking cam when the hour is to be struck, the purpose of which is to align the teeth of the strike and chime gear Wheels so that they evenly engage the teeth of the driving gear wheel 5.

The striking mechanism follows standard practice, in that it consists of a snail 31 carried upon the sleeve 6 and a pivotally mounted rack 32 which falls upon the snail when the rack supporting lever 33 is swung from the position shown in full lines in Figure 2 to the position shown in dotted lines under the action of a pin 34 carried upon the back face of the rack lift cam and which engages a curved face 35 upon the rack supporting lever 33. An L-shaped lever 36 is pivoted upon the plate 3 to be actuated through its lower end being swung by the rack lift cam 26. A rack lift lever assembly 37 is pivoted upon the plate 3 to rest upon the upper leg of the lever 36 and whereby the oscillating movement of the lever 36 oscillates the assembly 37 to raise the rack after it has fallen. The foregoing described strike release and governing mechanism is a standard arrangement very well known.

The striking hammer 38 is preferably positioned underneath the rack supporting lever 33, the tail of the hammer being formed with a depression 39 in its outer end and in which the lower end of the lever 33 seats when the clock is running between the hours. The chime gear wheel 15 and striking gear wheel 22 are so arranged that as the clock is approaching the hour, the drop of the plunger causes the chime wheel to be moved into mesh with the rotating gear 5 whereby the partial rotation of the chime wheel causes the chime pin wheel 16 to partly rotate and chime the hour. In concluding the hour chiming movement the lug 29 on the chime wheel 15 is so positioned that it impacts the lug 30 on the striking cam whereby the unit formed by the striking cam, striking gear and rack lift cam is partially rotated to bring the striking wheel 22 into mesh with the gear 5. When this occurs, the striking wheel, striking cam and rack lift cam commence to rotate, thus causing the rack supporting lever 33 to swing under the impact of the pin 34 on the rack lift cam and disengage from the hammer 33 and allow the rack 32 to fall. When the rack 32 has been fully raised upon completion of the striking, the lever 33 will return to its normal position under the influence of its spring 40, at which time the striking gear 22 will have turned through a complete revolution wherein its gap 24 is again opposite the rotating gear 5. The hammer is actuated by the rotation of the toothed striking cam 25 in the standard fashion, the hammer in its downward swing contacting a buffer spring 41 to dampen its vibrations.

In Figures 7 and 8 a striking clock arrangement is shown wherein the clock strikes the hour. In this case, the four pointed star wheel 8 is replaced by a single pointed star wheel 42, and the four pointed star wheel 12 replaced by a single pointed star wheel 43. The star wheel 43 and the unit formed by the striking cam 25, strike wheel 22, and rack lift cam 26 as previously described, are mounted upon a sleeve 44 rotatable upon a spindle 45.

The lever 10 is raised and dropped once an hour on the hour and at which time the plunger 20 impacts the point 46 of the star wheel 43 to cause the assembly on the sleeve 44 to partially rotate and bring the teeth on the strike wheel into mesh with the teeth of the driving gear 5. When this occurs, the striking mechanism goes through the same motions as previously described, and upon completion of the striking, the striking wheel will have made one revolution and be stationary with its gap opposite the gear wheel 5 and the point 46 of the star wheel 43 returned to the position shown in Figure 7.

To overcome any possibility of binding of the gear teeth when passing into and out of mesh, the teeth of the chime and strike wheels are slightly thinner than the teeth on the driving gear, though, of course, having the same pitch.

In order to prevent vibration or jarring movement from starting the chime or striking motions, a steady disc 47, as illustrated in Figures 3, 6 and 8, is mounted to rotate with the motions exteriorly of the plate 3. In a chime clock, the disc has four peripheral notches 48, and in a striking clock, one peripheral notch 48. A pawl 49 rests in one of the notches 48 during the periods between chiming or striking and thus keeps the mechanism stationary against accidental displacement. When the mechanism is actuated its motion is sufficient to rotate the steady disc 47 against the spring action of the pawl.

From the foregoing description it will be apparent that I have devised a very simple chiming and striking mechanism for electric clocks driven by continuously rotating synchronous motors, and wherein I utilize a very simple lift and drop mechanism for bringing the striking and chiming gear trains into mesh with the continuously rotating clock driving gear wheel, and although I have shown and described a particular embodiment and construction of my invention, it will be appreciated that it is susceptible to a number of changes and variations without departing from the spirit of my invention as set forth in the appended claims.

What I claim as my invention is:

1. An audible signal controlling and operating mechanism for an electric clock having a continuously rotated gear wheel driven by an electric motor, and comprising a gear wheel for driving the signal mechanism and positioned to intermittently mesh with said rotated gear wheel and having a gap in its teeth whereby said gear wheel is stationary when its gap is opposite to the teeth of the rotated gear wheel, and a signal actuating mechanism intermittently operated by the rotated gear wheel for moving said signal mechanism driving gear wheel from a stationary position into a meshing position with said rotated gear wheel.

2. An arrangement as defined in claim 1, wherein the signal mechanism intermittently actuated by the rotated gear wheel comprises an element lifted and allowed to drop immediately prior to the time of the signal, said element in its drop moving the signal mechanism driving gear wheel into mesh with the rotated gear wheel.

3. An arrangement as defined in claim 1, wherein the signal mechanism intermittently actuated by the rotated gear wheel comprises a continuously rotated star wheel, a drop arm raised to its dropping point by the star wheel, a rotatable element coupled to and rotatable with the signal mechanism driving gear wheel, and means carried by the drop arm for impacting and rotating the rotatable element and the signal mechanism driving gear wheel into mesh with the rotated gear wheel after said drop arm has dropped.

4. An arrangement as defined in claim 1, wherein the signal mechanism intermittently actuated by the rotated gear wheel comprises a continuously rotated star wheel, a drop arm raised to its dropping point by the star wheel, a second star wheel rotatable in unison with the signal mechanism driving gear wheel, and a pendant plunger arm carried by the drop arm for impacting and rotating the second star wheel and the signal mechanism driving gear wheel into mesh with the continuously driven gear wheel after said drop arm has dropped.

5. A striking and chiming signal controlling and operating arrangement for an electric clock having a continuously rotated gear wheel driven by an electric motor, and comprising a gear wheel for driving the striking mechanism and having a gap in its teeth, a gear wheel for driving the chime mechanism and having several spaced apart gaps in its teeth, said gears wheels being positioned to mesh with the rotated gear wheel and to pass out of mesh therewith through the medium of the gaps in their teeth, and a signal actauting mechanism intermittently operated by the rotated gear wheel for moving said chime mechanism gear wheel from a stationary position with one of its gaps opposite the teeth of the rotated gear wheel into mesh with the rotated gear wheel, and means on said chime mechanism driving gear wheel for rotating the strike mechanism driving gear wheel into mesh with the rotated gear wheel once in everyrevolution of said chime mechanism gear wheel.

6. An arrangement as defined in claim 5 wherein the signal mechanism intermittently actuated by the rotated gear wheel comprises an element lifted and allowed to drop immediately prior to the chiming signal, said element in its drop moving the chiming mechanism driving gear wheel into mesh with the rotated gear wheel.

7. An arrangement as defined in claim 5 wherein the signal mechanism intermittently actuated by the rotated gear wheel comprises a continuously rotated star wheel, a drop arm raised to its dropping point by the star wheel, a rotatable element coupled to and rotatable with the chiming mechanism driving gear wheel, and means carried by the drop arm for impacting and rotating the rotatable element and the chiming mechanism gear wheel into mesh with the rotating gear wheel after said drop arm has dropped.

8. An arrangement as defined in claim 5 wherein the signal mechanism intermittently actuated by the rotated gear wheel comprises a continuously rotated star wheel, a drop arm raised to its dropping point by the star wheel, a second star wheel rotatable in unison with the chiming mechanism driving gear wheel, and a pendant plunger arm carried by the drop arm for impacting and rotating the second star wheel and the chiming mechanism driving gear wheel into mesh with the rotating gear wheel after said drop arm has dropped.

9. A striking and chiming signal controlling and operating arrangement for an electric clock having a continuously rotated gear wheel driven by an electric motor, and comprising a gear wheel for driving the chime mechanism and having several spaced apart gaps in its teeth and positioned to mesh with the rotated gear wheel and to pass out of mesh therewith through the medium of the gaps in its teeth, a gear wheel for driving the striking mechanism, and a signal actuating mechanism intermittently operated by the rotated gear wheel for moving said chime mechanism gear wheel from a stationary position with one of its gaps opposite the teeth of the rotated gear wheel into mesh with the rotated gear wheel, and means on said chime mechanism driving gear wheel for rotating the striking mechanism driving gear wheel once in every revolution of said chime mechanism gear wheel.

10. A striking and chiming signal controlling and operating arrangement for an electric clock having a continuously rotated gear wheel driven by an electric motor, and comprising a gear wheel for driving the chime mechanism and having several spaced apart gaps in its teeth and positioned to mesh with the rotated gear wheel and to pass out of mesh therewith through the medium of the gaps in its teeth, a gear wheel for driving the striking mechanism, and a signal actuating mechanism intermittently operated by the rotated gear wheel for moving said chime mechanism gear Wheel from a stationary position with one of its gaps opposite the teeth of the rotated gear wheel into mesh with the rotated gear wheel, and means on said chime mechanism driving gear wheel for moving the striking mechanism driving gear wheel into mesh with the rotated gear wheel once in every revolution of said chime mechanism gear wheel.

11. A striking and chiming signal controlling and operating arrangement for an electric clock having a continuously rotated gear wheel driven by an electric motor, and comprising a gear wheel for driving the striking mechanism and having a gap in its teeth, a gear wheel for driving the chime mechanism and having several spaced apart gaps in its teeth, said gear wheels being positioned to mesh with the rotated gear wheel and to pass out of mesh therewith through the medium of the gaps in their teeth, and a signal actuating mechanism intermittently operated by the rotated gear wheel for moving said chime mechanism gear wheel from a stationary position with one of its gaps opposite the teeth of the rotated gear wheel into mesh with the rotated gear Wheel, a lug on the chime mechanism driving gear wheel, a lug for rotating the striking mechanism driving gear wheel and positioned to be impacted by the lug on the chime gear wheel once in every revolution of the chime gear wheel and whereby the strike driving gear wheel is moved into mesh with the rotated gear wheel to rotate therewith.

References Cited in the file of this patent UNITED STATES PATENTS 2,081,289 Ayres May 25, 1937 FOREIGN PATENTS 647,930 France Aug. 6, 1928 319,240 Great Britain Dec. 10, 1930 392,741 Great Britain May 25, 1933 

